1.Single solid nodule more than 1 cm in size. 2.Single solid nodule less than 1 cm but with calcification or abnormal blood flow or lymph node enlargement. 3.Single cyst more than 2-3 cm in size. 4.Multiple nodules in which the largest nodule is more than 2 cm or nodules with calcification or abnormal blood flow or lymph node enlargement. 5, Thyroid nodule with previous history of neck radiation exposure or treatment. 7.Posterior sternal goiter. 8, Sudden recent enlargement of thyroid nodules. 9. Thyroid nodules with pressure, voice changes, swallowing difficulties and irritating cough.